Figuring out what realms had what resource and where was a big part of exploration and what made the various biomes and their peculiarities compelling.
The previous ore generation may have been a little too fiddly with the Realm Level variance, but this tier-based system goes too far in the other direction, making finding various ores incredibly dull. It basically amounts to running in any direction out of the portal and then mining everything you see for 10 minutes to be set for the current tier (throw in the occasional cave for that couple of extra resources per tier).
Especially now with the Storied Realms being able to guarantee certain resources are available to players through their mandatory progression unlocks, it's extra disappointing that this was the solution to people not finding iron or whatever.
I'm totally in agreement. It seems to me that the main attraction of this game was exploration; we had the feeling that there were an infinite number of different realms, and we had to visit many to find different merchants and different resources depending on the main type (Forest, Swamp, Desert) and the level, which was affected by the secondary type (Herbarium, Astrolab, etc.). Now we see these same green and blue minerals everywhere all the time. By trying too hard to simplify everything to satisfy the complainers, you end up betraying the soul of your creation; exploration tends to become a totally negligible aspect, and that's sad.